if you are using OS3.9 you already have SquirrelJazTools (Tools/Commodities) that helps you with both Jaz and Zip drives.
if you don't look on aminet for things like
ZipTool12.lha.
altho, you may want to check out other files. there are several mount files out there, depending on the size of the zip disk.
and don't forget to use fat95. my experiance is to never format a zip in anything but fat as the most common use is to move files between AMiga and some stupid PC.
but you may have other plans. anyway, fat95 is just plain good!